1. Field of the Invention
The present invention relates to a CD player and, more particularly, to a CD player apparatus suitable for a CD player for outdoor use of which an improved shockproof property is required.
2. Description of the Related Art
CD players of the type in which a laser spot is thrown on pits formed on a compact disk and the reflected beam therefrom is detected and information recorded on the compact disk is thereby reproduced are in practical use now.
The CD player of such type is provided, between the disk and the optical pickup, with a focus servo for forming the image of the laser spot right on the signal recording surface of the disk at all times, a tracking servo causing the laser spot to correctly track the pit train, a motor servo for rotating the disk at the right speed of rotation corresponding to the position of the pickup, a feed servo for allowing the optical pickup to access a desired position, etc. Thus, the disk and the pickup are controlled strictly to keep predetermined relative position at all times.
Accordingly, the CD player in practical use today can perform its playback operation well even under a certain amount of external force. It can be especially strengthened against rolling. However, when the external force exceeds certain limit, it sometimes cause the disk and the optical pickup to deviate from the predetermined relative position, i.e., to cause what is called a track jump.
When such track jump occurs, the reproduced RF signal breaks its continuity and, hence, there has been a problem that a dropout is produced while for example music is being played back. Thus, there is a limit to the improvement of the shockproof property of the CD player achievable only by the reinforcement, as hitherto carried out, of servo mechanisms, and it has been impossible to greatly improve the shockproof property of CD players for outdoor use such as on-vehicle CD players and portable CD players. Hence, it has been unachievable to fabricate a portable CD player with such an excellent shockproof property that a jogger for example can use it while jogging.